摘要
选用三柱塞泵,建立有机朗肯循环（ORC）实验平台。选用涡旋式膨胀机作为热功转换设备,采用三氟二氯乙烷（R123）作为工质,在140℃热源下开展实验,考察工质泵在不同工况下的运行性能。研究结果表明,三柱塞泵实际运行效率为22%-30%,是已有文献报道水平的1.5-4.3倍。工质泵等熵效率和机械效率分别为60%-69%和37%-45%。工质泵运行参数偏离额定参数是导致机械效率偏低的主要原因。工质泵发生气蚀会导致其等熵效率减小,同时还会造成工质流量下降。对于本实验台,防止气蚀发生的工质泵入口临界过冷度为21℃。
The organic Rankine cycle （ORC） is one of the key technologies to fulfill the efficient utilization of low grade heat sources. Working fluid circulating pump is the main power consumption component of ORC system. However, the overall pump efficiency as low as 7% -20% was reported in the experimental study. To solve this problem, an experimental system for heat recovery from low grade heat source was constructed, R123 was selected as working fluid, a scroll expander was used to produce work, and a tri-plunger pump was selected as working fluid circulating pump. The conductive oil was heated by electric heater to simulate low grade heat source. The maximum expander shaft power and thermal efficiency were 2. 16 kW and 5.35% at the heat source temperature of 140~C, respectively. The range of overall pump efficiency was about 22% - 30% , which was 1.5 - 4. 3 times of that reported in the references. The isentropic efficiency and mechanical efficiency of the pump were 60% ~ 69% and 37% ~45%, respectively. Analysis results showed that the reason for low mechanical efficiency of the pump was due to the fact that the pump operating parameters were deviated far from the rated parameters. Additionally, cavitation could weaken pump isentropic efficiency and reduce the working fluid flow rate at the same time. Critical sub-cooling temperature as high as 21~C was obtained at the pump inlet to prevent the cavitation. The study results identified that tri-plunger pump can be recommended in the ORC system.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2015年第8期367-371,378,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家重点基础研究发展计划(973计划)资助项目(2011CB710703)
国家自然科学基金国际合作与交流资助项目(51210011)
中央高校基本科研业务费专项资金资助项目(JB2014215)
关键词
三柱塞泵
低品位热源
有机朗肯循环
泵效率
临界过冷度
Tri-plunger pump Low grade heat source Organic Rankine cycle Pump efficiency Critical sub-cooling
